THEERTHA PRASAD, D.VINAY KUMAR, G. S.2017-07-102017-07-102015-01-12Th-10985http://krishikosh.egranth.ac.in/handle/1/5810024776Environmental degradation and abiotic stresses such as drought, high temperature, and salinity affect the plant growth and development. Environmental factors are known sources for oxidative stress. These stresses involve enhanced production of reactive oxygen species (ROS) like hydrogen peroxide, superoxide etc. NDPKs are multi functional proteins that play an important role in cellular signalling processes involving regulation of ROS levels. Study was conducted using yeast strains W3O3 (wild type) and ΔYNK (mutant). ΔYNK was highly susceptible to ROS compared to W3O3 based on Microbial growth rate, Doubling time, Percentage of Total soluble protein, Thermo-stable protein and Percentage decrease in NADH concentration. Significant increase in growth pattern was observed in W3O3 compare to ΔYNK. More drastic reduction in Total soluble protein and Thermo-stable protein was observed in ΔYNK than W3O3 cells upon H2O2 treatment followed by 350C, 400C and 50C. Among different stress H202 treated cells show less Thermo-stable protein. Induction of both thermal and ROS stress results in depletion of NADH levels, among these 350C, 50C treated ΔYNK cells produce significant reduction in NADH level as compare to H2O2 treatment. These results put together suggest that YNK is important for cellular metabolism and play major role in NADH production which provide reductants to maintain yeast cells during oxidant stress and there by provide protection. Deletion of YNK results in down regulation of certain ROS induced and heat stable proteins this will deplete the NADH level which could be the part of cellular signalling cascade.ennullThesis